The efficiency of estrogens in the treatment of hormone-deficiency-induced symptoms such as hot flashes, atrophy of estrogen target organs and incontinence, as well as the successful use of estrogen therapies for prevention of bone mass loss in peri- and postmenopausal women, is well documented and generally accepted (Grady et al. 1992, Ann Intern Med 117:1016-1037). It is also well documented that estrogen replacement therapy in postmenopausal women or in women with ovarian dysfunction that is caused in some other way reduces the risk of cardiovascular diseases compared to women who are not treated with estrogen (Grady et al., loc. cit.).
In conventional estrogen or hormone replacement therapy (=HRT), natural estrogens, such as estradiol, and conjugated estrogens that consist of equine urine are used either by themselves or in combination with a gestagen. Instead of the natural estrogens, derivatives that are obtained by esterification, such as, e.g., 17β-estradiol-valerate, can also be used.
Because of the stimulating action of the estrogens that are used on the endometrium, which results in an increase of the risk of endometrial carcinoma (Harlap, S. 1992, Am J Obstet Gynecol 166:1986-1992), estrogen/gestagen combination preparations are preferably used in hormone replacement therapy. The gestagenic component in the estrogen/gestagen combination avoids hypertrophy of the endometrium, but the occurrence of undesirable intracyclic menstrual bleeding is also linked to the gestagen-containing combination.
Selective estrogens represent a more recent alternative to the estrogen/gestagen combination preparations. Up until now, selective estrogens have been defined as those compounds that have an estrogen-like effect on the brain, bones and vascular system, owing to their antiuterotropic (i.e., antiestrogenic) partial action, but they do not have a proliferative effect on the endometrium.
A class of substances that partially meet the desired profile of a selective estrogen is the so-called “Selective Estrogen Receptor Modulators” (SERM) (R. F. Kauffman, H. U. Bryant 1995, DNAP 8 (9):531-539). In this case, these are partial agonists of estrogen receptor subtype “ERα.” This substance type is ineffective, however, with respect to the therapy of acute postmenopausal symptoms, such as, e.g., hot flashes. As an example of a SERM, the raloxifene that was recently introduced for the indication of osteoporosis can be mentioned.
For the treatment of fertility disorders of women, frequently caused by ovarian dysfunction that is caused by surgery, medication, etc., new possible therapies are also opened up by the use of new selective estrogens. The in-vitro fertility treatment is a process that has been established for more than 20 years. Numerous methods for treating ovarian-induced infertility with exogenic gonadotropins are known. By administration of gonadotropins such as FSH (FSH=follicle-stimulating hormone), a stimulation of the ovaries, which is to make possible a healthy follicular maturation, is to be produced.
The follicle is the functional unit of the ovary and has two purposes: it accommodates the oocytes and provides for the latter the possibility for growth and for maturation. Folliculogenesis comprises the development of an ovarian follicle from a primordial stage to a continuously increasing antral follicle, which represents the last stage before ovulation. Only an optimally developed antral follicle can release a mature ovocyte by ovulation.
Patients with ovarian-induced infertility (PCOS=syndrome of polycystic ovaries) suffer from a disrupted follicular maturation, which is associated both with hormonal and ovulatory disruptions and with inadequately matured ovocytes. The number of primary and secondary follicles is approximately twice as high here as in the normal ovary (Hughesden et al., Obstet. Gynecol. Survey 37, 1982, pp. 59-77).
There are indications that the early development stages of folliculogenesis (which relates to the development of primordial follicles to antral follicles) are gonadotropin-independent. It is not clearly explained how great the influence of known paracrine and autocrine factors is on early folliculogenesis (Elvin et al., Mol. Cell Endocrinol. 13, 1999, pp. 1035-1048; McNatty et al., J. Reprod. Fertil. Suppl. 54, 1999, pp. 3-16).
Gonadotropins such as FSH are mainly involved in the last development stages of folliculogenesis in follicular maturation, i.e., in the development of the early antral follicle to a mature follicle that can undergo ovulation.
The in-vivo and in-vitro infertility is preferably treated with gonadotropins (FSH and antiestrogens) (White et al., J. Clin. Endocrinol. Metab. 81, 1996, pp. 3821-3824). In in-vitro fertilization treatment, oocytes are removed from preovulatory antral follicles to be able to mature in vitro into an ovocyte that can be fertilized. After fertilization and preembryonal development, one to three embryos are implanted in the uterus of the woman.
In many respects, the treatment with exogenic gonadotropins is accompanied by numerous risks and side effects. The greatest risk consists in an overstimulation of the ovaries, which in severe cases can represent a serious danger to life (OHSS=Ovarian Hyperstimulation Syndrome). Other side effects are the high costs of the in-vitro fertility treatment that must be paid by the coupled. Negative side effects such as weight gain, bloatedness, nausea, vomiting and an as yet unknown long-term risk of developing cancer are attributed to the gonadotropin treatment.
One method to avoid the above-mentioned drawbacks and risks is to ensure the maturation and stimulation in vivo of follicular growth in the case of ovarian-induced infertility with a suitable active ingredient before treatment with exogenic gonadotropins begins.
Estrogen Receptor Beta (ERβ)
Several years ago, estrogen receptor β (ERβ) was discovered as a second subtype of the estrogen receptor (Kuiper et al. (1996), Proc. Natl. Acad. Sci. 93:5925-5930; Mosselman, Dijkema (1996) Febs Letters 392:49-53; Tremblay et al. (1997), Molecular Endocrinology 11:353-365). The expression pattern of ERβ differs from that of the ERα (Kuiper et al. (1996), Endocrinology 138:863-870). ERβ thus predominates over ERα in the rat prostate, while ERα predominates over ERβ in the rat uterus. The highest concentrations of ERβ and mRNA were found in the ovaries (Couse et al. Endocrinology 138, 1997, pp. 4612-4613).
Other organ systems with comparatively higher ERβ-expression comprise the bones (Onoe, Y. et al., 1997, Endocrinology 138:4509-4512), the vascular system (Register, T. C., Adams, M. R. 1998, J. Steroid Molec Biol 64:187-191), the urogenital tract (Kuiper, G. J. M. et al. 1997, Endocrinology 138:863-870), the gastrointestinal tract (Campbell-Thopson 1997, BBRC 240:478-483), as well as the testis (Mosselmann, S. et al. 1996 FEBS Lett. 392, 49-53) including the spermatides (Shugrue et al. 1998, Steroids 63:498-504). The tissue distribution suggests that estrogens regulate organ functions via ERβ. The fact that ERβ is functional in this respect also follows by studies in ERα-(ERKO) or ERβ-(βERKO)-knockout mice: ovariectomy produces bone mass loss in ERKO-mice, which can be eliminated by estrogen substitution (Kimbro et al. 1998, Abstract OR7-4, Endocrine Society Meeting, New Orleans). Estradiol in the blood vessels of female ERKO mice also inhibits vascular media and smooth muscle cell proliferation (Iafrati, M. D. et al. 1997, Nature Medicine 3:545-548). These protective actions of estradiol are carried out in the ERKO mouse presumably via ERβ.
The fact that ERα and ERβ have a functionally different action was confirmed after successful production of αERKO and βERKO mice. ERα consequently plays an important role in the adult uterus, in mammary gland tissue, in the negative regulation of the gonadotropin activity, while ERβ is mainly bonded in the processes of ovarian physiology, especially that of folliculogenesis and ovulation (Couse et al., Endocrine Reviews 20, 1999, pp. 358-417).
Observations of βERKO mice provide an indication on a function of ERβ in the prostate and bladder: in the case of older male mice, symptoms of prostate and bladder hyperplasia occur (Krege, J. H. et al. 1998, Proc Natl Acad Sci 95:15677-15682). In addition, female ERKO mice (Lubahn, D. B. et al. 1993, Proc Natl Acad Sci 90:11162-11166) and male ERKO mice (Hess, R. A. et al. 1997, Nature 390:509-512) as well as female βERKO mice (Krege, J. H., 1998, Proc Natl Acad Sci 95:15677-15682) have fertility disorders. Consequently, the important function of estrogens with respect to maintaining testis and ovary functions as well as fertility is confirmed.
It was possible to achieve a selective estrogenic action on specific target organs by subtype-specific ligands based on the different tissue or organ distribution of the two subtypes of the ERs. Substances with a preference for ERβ compared to ERα in the in-vitro receptor binding test were described by Kuiper et al. (Kuiper et al. (1996), Endocrinology 138:863-870). A selective action of subtype-specific ligands of the estrogen receptor on estrogen-sensitive parameters in vivo was not previously shown.
The object of this invention is therefore to prepare compounds that have in vitro a dissociation with respect to the binding to estrogen receptor preparations from rat prostates and rat uteri. The compounds are to show in vitro a higher affinity to estrogen receptor preparations from rat prostates than to estrogen receptor preparations from rat uteri.
The ERβ-specific compounds are to produce in vivo a profertility action in the ovary. At the same time, the compounds are to exhibit a dissociation with respect to ovary action in comparison to uterus action. The compounds according to the invention are to have a certain protective action against hormone-deficiency-induced bone mass loss in comparison to uterus-stimulating action.
In the broader sense, a structure-action relationship, which allows for access to compounds that have the above-formulated pharmacological profile, is to be made available by this invention. The compounds according to the invention are to produce enhanced fertility in the ovary while at the same time affecting the uterus very little in cases of ovarian-associated infertility.
According to the invention, the object above is achieved by the provision of 9α-substituted estra-1,3,5(10)-triene derivatives of general formula I
in which radicals R3, R7, R7′, R9, R13, R16 as well as R17 and R17′, independently of one another, have the following meaning:                R3 means a hydrogen atom or a group R18, in which                    R18 means a straight-chain or branched-chain, saturated or unsaturated hydrocarbon radical with up to 6 carbon atoms, a trifluoromethyl group, an optionally substituted aryl, heteroaryl or aralkyl radical, an acyl radical COR19, in which R19 is an optionally substituted, straight-chain or branched-chain hydrocarbon radical with up to 10 carbon atoms that is saturated or unsaturated in up to three places and optionally partially or completely halogenated, or            R18 means a group R20SO2, in which                            R20 is an R21R22N group, whereby R21 and R22, independently of one another, mean a hydrogen atom, a C1-C5-alkyl radical, a group C(O)R23, in which R23 means an optionally substituted, straight-chain or branched-chain hydrocarbon radical with up to 10 carbon atoms that is saturated or unsaturated in up to three places and is optionally partially or completely halogenated, an optionally substituted C3-C7-cycloalkyl radical, an optionally substituted C4-C15-cycloalkylalkyl radical or an optionally substituted aryl, heteroaryl or aralkyl radical, or, together with the N atom, a polymethylenimino radical with 4 to 6 C atoms or a morpholino radical,                                                R7 and R7′, in each case independently of one another, are a hydrogen atom or a halogen atom,        R9 is a straight-chain or branched-chain alkenyl or alkinyl radical with 2 to 6 carbon atoms, which optionally can be partially or completely fluorinated,        R13 is a methyl group or an ethyl group,        R16 is a hydroxy group or a group R18O—, R20SO2— or OC(O)R23 with R18, R20 and R23 in each case in the meaning that is indicated under R3,        R17 and R17′, in each case independently of one another, are a hydrogen atom or a halogen atom,        R16 can in each case be in α- or β-position.        
According to a variant of the invention, gonatriene derivatives are preferred, in which R7 and R7′ are a hydrogen atom, R9 is a vinyl, ethinyl or prop-1-inyl group, R16 is a hydroxy group, and R17 and R17′ in each case are a hydrogen atom.
In addition, the following combinations of halogen substitution, preferably fluorine, in C-atoms 7 and 17 are preferred: 7-mono or 7-di and R17 as well as R17′, in each case a hydrogen, 17-mono or 17-di and R7 as well as R7′, in each case a hydrogen as well as 7-mono/17-mono, 7-mono/17-di, 7-di/17-mono, 7-di/17-di. The 7α-position or the 17β-position is preferred in the monofluorine compounds.
Another variant of the invention in particular calls for compounds in which R16 stands for a group R18O— or R20SO2—O— with R18 and R20 in each case in the meaning that is indicated under R3.
Preferred according to this invention are the following compounds:                9α-Vinyl-estra-1,3,5(10)-triene-3,16α-diol        9α-Allyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-9α-allyl-estra-1,3,5(10)-triene-3,16α-diol        3-Methoxy-9α-vinyl-estra-1,3,5(10)-trien-16α-ol        9α-Allyl-3-methoxy-estra-1,3,5(10)-trien-16α-ol        18a-Homo-3-methoxy-9α-vinyl-estra-1,3,5(10)-trien-16α-ol        18a-Homo-9α-allyl-3-methoxy-estra-1,3,5(10)-trien-16α-ol        9α-(2′,2′-Difluorovinyl)-estra-1,3,5(10)-triene-3,16α-diol        9α-(2′,2′-Difluorovinyl)-3-methoxy-estra-1,3,5(10)-trien-16α-ol        16α-Hydroxy-9α-vinyl-estra-1,3,5(10)-trien-3yl-sulfamate        9α-Allyl-16α-hydroxy-estra-1,3,5(10)-trien-3yl-sulfamate        18a-Homo-16α-hydroxy-9α-vinyl-estra-1,3,5(10)-trien-3yl-sulfamate        18a-Homo-9α-allyl-16α-hydroxy-estra-1,3,5(10)-trien-3yl-sulfamate        9α-Vinyl-estra-1,3,5(10)-triene-3,16α-diyl-disulfamate        9α-Allyl-estra-1,3,5(10)-triene-3,16α-diyl-disulfamate        18a-Homo-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diyl-disulfamate        18a-Homo-9α-allyl-estra-1,3,5(10)-triene-3,16α-diyl-disulfamate        16α-Hydroxy-9α-vinyl-estra-1,3,5(10)-trien-3yl-(N-acetyl)-sulfamate        9α-Allyl-16α-hydroxy-estra-1,3,5(10)-trien-3yl-(N-acetyl)-sulfamate        18a-Homo-16α-hydroxy-9α-vinyl-estra-1,3,5(10)-trien-3yl-(N-acetyl)-sulfamate        18a-Homo-9α-allyl-16α-hydroxy-estra-1,3,5(10)-trien-3yl-(N-acetyl)-sulfamate        9α-(Prop-(Z)-enyl)-estra-1,3,5(10)-triene-3,16α-diol        9α-(n-Propyl)-estra-1,3,5(10)-triene-3,16α-diol        9α-Ethinyl-estra-1,3,5(10)-triene-3,16α-diol        9α-Vinyl-estra-1,3,5(10)-triene-3,16α-diol-diacetate        18a-Homo-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol-diacetate        16α-Valeroyloxy-9α-vinyl-estra-1,3,5(10)-trien-3-ol        16α-Acetoxy-9α-vinyl-estra-1,3,5(10)-trien-3-ol        18a-Homo-16α-acetoxy-9α-vinyl-estra-1,3,5(10)-trien-3-ol        7α-Fluoro-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol        7α-Fluoro-9α-allyl-estra-1,3,5(10)-triene-3,16α-diol        17β-Fluoro-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol        17β-Fluoro-9α-allyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-7α-fluoro-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-7α-fluoro-9α-allyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-17β-fluoro-9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol        18a-Homo-17β-fluoro-9α-allyl-estra-1,3,5(10)-triene-3,16α-diol        
Other possible configurations of this invention will emerge from the subclaims.
Hydrocarbon radical R18 is, for example, a methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert.-butyl, pentyl, isopentyl, neopentyl, or hexyl radical.
Alkoxy groups OR18 in the compounds of general formula I in each case can contain 1 to 6 carbon atoms, whereby methoxy, ethoxy, propoxy, isopropoxy and 1-butyloxy groups are preferred.
Representatives of the C1-C5-alkyl radicals R21 and R22 are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl and neopentyl.
As representatives of straight-chain or branched-chain hydrocarbon radicals R22 with 1 to a maximum of 10 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, heptyl, hexyl, and decyl can be mentioned; methyl, ethyl, propyl and isopropyl are preferred.
As a C3-C7-cycloalkyl group, a cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or cycloheptyl group can be mentioned.
A C4-C15-cycloalkylalkyl radical has 3 to 7 carbon atoms in the cycloalkyl portion; typical representatives are the cycloalkyl groups that are mentioned directly above. The alkyl portion has up to 8 carbon atoms.
As examples of a C4-C15-cycloalkylalkyl radical, the cyclopropylmethyl, cyclopropylethyl, cyclopentylmethyl, cyclopentylpropyl groups, etc., can be mentioned.
In terms of this invention, an aryl radical is a phenyl, 1- or 2-naphthyl radical; the phenyl radical is preferred.
Aryl always also includes a heteroaryl radical. Examples of a heteroaryl radical are the 2-, 3- or 4-pyridinyl, the 2- or 3-furyl, the 2- or 3-thienyl, the 2- or 3-pyrrolyl, the 2-, 4- or 5-imidazolyl, the pyrazinyl, the 2-, 4- or 5-pyrimidinyl or 3- or 4-pyridazinyl radical.
As substituents that can be present on an aryl or heteroaryl radical, for example, a methyl-, ethyl-, trifluoromethyl-, pentafluoroethyl-, trifluoromethylthio-, methoxy-, ethoxy-, nitro-, cyano-, halogen- (fluorine, chlorine, bromine, iodine), hydroxy-, amino-, mono(C1-8 alkyl) or di(C1-8 alkyl)amino, whereby both alkyl groups are identical or different, di)aralkyl)amino, whereby both aralkyl groups are identical or different, carboxyl, carboxyalkoxy, C1-C20-acyl or C1-C20-acyloxy groups can be mentioned.
An aralkyl radical is a radical that contains in the ring up to 14, preferably 6 to 10, C atoms, and in the alkyl chain 1 to 8, preferably 1 to 4, C atoms. Thus, as aralkyl radicals, for example, benzyl, phenylethyl, naphthylmethyl, naphthylethyl, furylmethyl, thienylethyl, and pyridylpropyl are suitable.
The alkyl groups or hydrocarbon radicals can be partially or completely substituted by 1-5 halogen atoms, hydroxy groups or C1-C4-alkoxy groups.
A vinyl or allyl radical is primarily defined with a C2-C6-alkenyl radical.
A C2-C6-alkinyl radical is preferably defined as an ethinyl radical or a prop-1-inyl radical.
C1-10-Acyl radicals mean, for example, acetyl, propionyl, butyryl, valeroyl, isovaleroyl, pivaloyl, hexanoyl, octyl, nonyl, or decanoyl.
One or two hydroxyl groups at C atoms 3 and 16 can be esterified with an aliphatic, straight-chain or branched-chain, saturated or unsaturated C1-C14-mono- or polycarboxylic acid or an aromatic carboxylic acid.
Suitable as such carboxylic acids for esterification are, for example:
Monocarboxylic acids: formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, lauric acid, myristic acid, acrylic acid, propionic acid, methacrylic acid, crotonic acid, isocrotonic acid, oleic acid, and elaidic acid.
Esterification with acetic acid, valeric acid or pivalic acid is preferred.
Dicarboxylic acids: oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, maleic acid, fumaric acid, muconic acid, citraconic acid, and mesaconic acid.
Aromatic carboxylic acids: benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthoic acid, o-, m- and p-toluic acid, hydratropic acid, atropoic acid, cinnamic acid, nicotinic acid, and isonicotinic acid.
Esterification with benzoic acid is preferred.
As prodrugs, the esters of the 9α-substituted estratrienes according to the invention have advantages compared to the unesterified active ingredients with respect to their method of administration, their type of action, strength and duration of action.
Especially the sulfamates of 9α-substituted estratrienes according to the invention have pharmacokinetic and pharmacodynamic advantages. Related effects were already described in other steroid-sulfamates (J. Steroid Biochem. Molec. Biol, 55, 395-403 (1995); Exp. Opinion Invest. Drugs 7, 575-589 (1998)).
In this patent application, steroids on which the 9α-substituted estra-1,3,5(10)-triene skeleton is based are described for the treatment of estrogen receptor β-mediated disorders and conditions as selective estrogens, which have in-vitro dissociation with respect to their binding to estrogen receptor preparations from rat prostates and rat uteri and which have in vivo preferably a dissociation with respect to ovary action in comparison to uterus action. In addition, the compounds have a certain protective action against hormone-deficiency-induced bone mass loss.
It was found that the 9α-substituted estra-1,3,5(10)-trienes according to general formula I are suitable as selective estrogens for the treatment of various conditions and disorders that are characterized by a higher content of estrogen receptor β than estrogen receptor α in the corresponding target tissue or target organ.
The invention also relates to pharmaceutical preparations that contain at least one compound of general formula I (or physiologically compatible addition salts with organic and inorganic acids thereof) and the use of the compounds of general formula I for the production of pharmaceutical agents, especially for the indication mentioned below.
The new selective estrogens that are described here can be used as individual components in pharmaceutical preparations or in combination especially with gestagens. Especially preferred is the combination of selective estrogens with ERα-selective antiestrogens that are peripherally-selectively active, i.e., that do not pass through the blood-brain barriers, as well as with selective estrogen receptor modulators (SERM). The ERβ-selective compounds according to the invention can be used in particular for the production of pharmaceutical agents for treating fertility disorders, for prevention and therapy of prostate hyperplasia, for prevention and treatment of hormone-deficiency-induced mood swings in women and men and for use in hormone replacement therapy (HRT) in men and women.
A therapeutic product that contains an estrogen and a pure antiestrogen for simultaneous, sequential or separate use for the selective estrogen therapy of perimenopausal or postmenopausal conditions is already described in EP-A 0 346 014.
Because of their dissociation of action in the ovary in comparison to the action of the uterus, the substances and the pharmaceutical agents that contain them are especially suitable for the treatment in the case of ovarian dysfunction that is caused by surgery, medication, etc., such as female infertility for stimulation of folliculogenesis for treatment by itself in terms of enhanced fertility, for supporting in-vitro fertility treatment (IVF) in connection with an in-vivo treatment and for treatment of ovarian-induced disorders in later age (“late fertility”) as well as for treatment of hormone-deficiency-induced symptoms.
The substances are also suitable for therapy of ovarian diseases such as polycystic ovarian syndrome, POF (premature ovarian failure) syndrome, and ovulation disorders.
Finally, the compounds of general formula I can be used in connection with selective estrogen receptor modulators (SERM) or raloxifene, specifically in particular for use in hormone replacement therapy (HRT) and for treatment of gynecological disorders.
The substances are also suitable as individual components for the treatment of perimenospausal and postmenopausal symptoms, in particular hot flashes, sleep disturbances, irritability, mood swings, incontinence, vaginal atrophy and hormone-deficiency-induced mental disorders. The substances are also suitable for hormone substitution and for the therapy of hormone-deficiency-induced symptoms in ovarian dysfunction that is caused by surgery, medication, etc.
In addition, the substances can also be used to prevent hormone-deficiency-induced bone mass loss and osteoporosis, to prevent cardiovascular system diseases, in particular vascular diseases such as arteriosclerosis, high blood pressure and to prevent hormone-deficiency-induced neurodegenerative diseases, such as Alzheimer's disease, as well as hormone-deficiency-induced impairment of memory and learning capacity.
In addition, the substances can be used as active ingredients in preparations for treating inflammatory diseases and diseases of the immune system, in particular autoimmune diseases, such as, e.g., rheumatoid arthritis, multiple sclerosis, lupus, Crohn's disease and other inflammatory intestinal diseases, inflammatory diseases of the skin, such as psoriasis, as well as for treating endometriosis.
In addition, the substances are effective against inflammatory diseases of the respiratory system, the lungs and bronchial tubes, such as, e.g., asthma.
The medication is suitable for therapy and prophylaxis of estrogen-deficiency-induced diseases both in women and in men.
In men, the compounds are especially suitable for therapy of hormone-deficiency-induced bone mass loss and osteoporosis, for prevention of cardiovascular diseases, in particular vascular diseases such as arteriosclerosis, high blood pressure and for prevention of hormone-deficiency-induced neurodegenerative diseases, such as Alzheimer's disease, as well as hormone-deficiency-induced impairment of memory and learning capacity, and are suitable for prevention and therapy of prostate hyperplasia.
The substances can be used for prophylaxis and therapy of age-related dysfunctions or diseases of men. In particular, they can be used for prevention and treatment of an age-related drop of androgens, such as testosterone and DHEA, as well as of the growth hormone.
In addition, the medication can be used for treating inflammatory diseases and diseases of the immune system, in particular autoimmune diseases in men, such as, e.g., rheumatoid arthritis, MS (multiple sclerosis) and Crohn's disease and other inflammatory intestinal diseases, as well as inflammatory diseases of the respiratory system, the lungs, and the bronchial tubes. The amount of a compound of general formula I that is to be administered fluctuates within a wide range and can cover any effective amount. On the basis of the condition that is to be treated and the type of administration, the amount of the compound that is administered can be 0.01 μg/kg—100 mg/kg of body weight, preferably 0.04 μg/kg—1 mg/kg of body weight, per day.
In humans, this corresponds to a dose of 0.8 μg to 8 g, preferably 3.2 μg to 80 mg, daily.
According to the invention, a dosage unit contains 1.6 μg to 2000 mg of one or more compounds of general formula I.
The compounds according to the invention and the acid addition salts are suitable for the production of pharmaceutical compositions and preparations. The pharmaceutical compositions or pharmaceutical agents contain as active ingredients one or more of the compounds according to the invention or their acid addition salts, optionally mixed with other pharmacologically or pharmaceutically active substances. The production of the pharmaceutical agents is carried out in a known way, whereby the known and commonly used pharmaceutical adjuvants as well as other commonly used vehicles and diluents can be used.
As such vehicles and adjuvants, for example, those are suitable that are recommended or indicated in the following bibliographic references as adjuvants for pharmaceutics, cosmetics and related fields: Ullmans Encyklopädie der technischen Chemie [Ullman's Encyclopedia of Technical Chemistry], Volume 4 (1953), pages 1 to 39; Journal of Pharmaceutical Sciences, Volume 52 (1963), page 918 ff., issued by Czetsch-Lindenwald, Hilfsstoffe für Pharmazie and angrenzende Gebiete [Adjuvants for Pharmaceutics and Related Fields]; Pharm. Ind., Issue 2, 1961, p. 72 and ff.: Dr. H. P. Fiedler, Lexikon der Hilfsstoffe für Pharmazie, Kosmetik und angrenzende Gebiete [Dictionary of Adjuvants for Pharmaceutics, Cosmetics and Related Fields], Cantor K G, Aulendorf in Württemberg 1971.
The compounds can be administered orally or parenterally, for example intraperitoneally, intramuscularly, subcutaneously or percutaneously. The compounds can also be implanted in the tissue.
For oral administration, capsules, pills, tablets, coated tablets, etc., are suitable. In addition to the active ingredient, the dosage units can contain a pharmaceutically compatible vehicle, such as, for example, starch, sugar, sorbitol, gelatin, lubricant, silicic acid, talc, etc.
For parenteral administration, the active ingredients can be dissolved or suspended in a physiologically compatible diluent. As diluents, very often oils with or without the addition of a solubilizer, a surfactant, a suspending agent or an emulsifying agent are used. Examples of oils that are used are olive oil, peanut oil, cottonseed oil, soybean oil, castor oil and sesame oil.
The compounds can also be used in the form of a depot injection or an implant preparation, which can be formulated so that a delayed release of active ingredient is made possible.
As inert materials, implants can contain, for example, biodegradable polymers, or synthetic silicones such as, for example, silicone rubber. In addition, for percutaneous administration, the active ingredients can be added to, for example, a patch.
For the production of intravaginal systems (e.g., vaginal rings) or intrauterine systems (e.g., pessaries, coils, IUDs, Mirena®) that are loaded with active compounds of general formula I for local administration, various polymers are suitable, such as, for example, silicone polymers, ethylene vinyl acetate, polyethylene or polypropylene.
To achieve better bio-availability of the active ingredient, the compounds can also be formulated as cyclodextrin clathrates. For this purpose, the compounds are reacted with α-, β-, or γ-cyclodextrin or derivatives of the latter (PCT/EP95/02656).
According to the invention, the compounds of general formula I can also be encapsulated with liposomes.
Methods
Estrogen Receptor Binding Studies
The binding affinity of the new selective estrogens was tested in competitive experiments with use of 3H-estradiol as a ligand to estrogen receptor preparations from rat prostates and rat uteri. The preparation of prostate cytosol and the estrogen receptor test with prostate cytosol was carried out as described by Testas et al. (1981) (Testas, J. et al., 1981, Endocrinology 109:1287-1289).
The preparation of rat uterus cytosol as well as the receptor test with the ER-containing cytosol were basically performed as described by Stack and Gorski (1985) (Stack, Gorski 1985, Endocrinology 117, 2024-2032) with some modifications as described in Fuhrmann et al. (1995) (Fuhrmann, U. et al. 1995, Contraception 51:45-52).
The substances that are described here have higher binding affinity to the estrogen receptor of rat prostates than to estrogen receptors of rat uteri. In this case, it is assumed that ERβ predominates in the rat prostates over ERα, and ERα predominates in rat uteri over ERβ. Table 1 shows that the ratio of the binding to prostate and uterus receptors qualitatively coincides with the quotient of relative binding affinity (RBA) to human ERβ and ERα of rats (according to Kuiper et al. (1996), Endocrinology 138:863-870) (Table 1).
TABLE 1hERαhERβERβ/Rat uterusRat prost.prost. ER/EstrogenRBA*RBA*ERαER(RBA)ER(RBA)uterus EREstradiol10010011001001Estrone60370.6320.817α-Estra-58110.22.41.30.5diolEstriol14211.542055-Andro-61730.1550stene-diolGenisteine53670.110100Coumes-9418521.32418trol*Cited from: Kuiper et al. (1996), Endocrinology 138: 863-870
Table 2 shows the results for 4 of the 9α-vinyl-estra-1,3,5(10)-triene-3,16α-diol derivatives (compounds 1; 2; 4; 5) according to the invention.
TABLE 2RBARBARatRatCompoundUterusProstate9α-Vinyl-estra-1,3,5(10)-3,16α-diol (1)1.21009α-Vinyl-estra-1,3,5(10)-17F-3,16α-diol (2)22009α-Di-F-Vinyl-estra-1,3,5(10)-3,16α-diol (4)0.249α-Di-F-Vinyl-estra-1,3,5(10)-13-Methyl-3,16α-diol0.26(5)
Compounds 1; 2; 4; 5 according to the invention show a higher binding affinity to the estrogen receptor of rat prostates than to the estrogen receptor of rat uteri.
In addition, the predictability of the prostate-ER versus the uterus-ER test system was confirmed with respect to tissue-selective action by in-vivo studies. Substances with a preference for prostate-ER are dissociated in vivo preferably with respect to ovary and uterus action as well as pituitary gland action in favor of action on the ovary.
Studies for Dissociation of Action of the Ovary/Uterus and Pituitary Gland
The studies with respect to the action on uterus growth and ovulation (indirect effect by influencing the secretion of pituitary gland hormones) are performed on adult female rats (body weight of 220-250 g). The substances are subcutaneously administered four times on four consecutive days. The first administration is carried out in the metestrus. One day after the last administration, the autopsy is carried out. The number of ovocytes in the tube (effect on the ovulation) as well as the uterus weight are determined.
While estradiol produces a dose-dependent ovulation inhibition and an increase in uterus weight with an ED50 of 0.004 mg/kg of body weight, substance 1 according to the invention up to a dose of 0.4 mg/kg of body weight does not exert any effect on ovulation and uterus weight.
Ovary Studies
The substances were tested in vivo on hypophysectomized juvenile rats. In a modification of this operative method, a GnRH antagonist is administered to the animals. It is examined whether the substance stimulates follicular proliferation (maturation) in the ovary. The ovary weight is the measurement parameter.
In each case, five animals (body weight 40-50 g) are assigned randomly to the treatment groups. The animals are fed as much as they want with a standard diet (altromin) in Makrolon cages in air-conditioned rooms with a lighting program (10 hours of darkness, 14 hours of light) and are given acidified tap water to drink. For the s.c. administration, the test substance as well as the control substance (estradiol E2) are dissolved in benzylbenzoate/castor oil (1+4 v/v).
Juvenile female rats are either hypophysectomized on day 0 and subcutaneously treated (administration 1×daily) from day 1 to day 4 with estradiol, compound 1 or 2 according to the invention, or subcutaneously treated (administration 1×daily) with a vehicle (castor oil/benzyl benzoate). In the modified version of the method, 0.5 mg/animal/day of Cetrorelix is administered to the animals simultaneously with compound 2 or the vehicle and the control substance estradiol over four days of treatment. In both cases, the animals are sacrificed 24 hours after the last administration, and the ovary weight is determined.
0.5 mg/animal/day of compound 1 that is administered subcutaneously over 4 days produces a comparable increase in ovary weight in hypophysectomized animals like estradiol with a dose of 0.1 mg/animal/day. The vehicle does not produce any effect.
Substance 1 according to the invention thus shows a clear dissociation of action in the ovary in comparison to the uterus action and the pituitary gland action and is excellently suited for the preferred indication, the treatment of female infertility, because of its follicle-stimulating action.
In the GnRH antagonist-treated animals, concentrations of 0.1 and 0.3 mg/animal/day of compound 2 in the ovary already show the same action as the dose of 1 mg/animal/day of estradiol that is used (FIG. 1). Even lower dosages (0.01, 0.03 mg/animal/day) show an ovary action and can eliminate the antagonistic effect of Cetrorelix (FIG. 2).
Key to FIG. 1:    Ovar=Ovary    Feuchtgewicht (%)=Moist weight (%)    0,1 mg=0.1 mg    0,3 mg=0.3 mg    1,0 mg=1.0 mg
Key to FIG. 2:    Ovar=Ovary    Feuchtgewicht (%)=Moist weight (%)    0,003 mg=0.003 mg    0,01 mg=0.01 mg    0.03 mg=0.03 mg    0,1 mg=0.1 mg
Substance 2 according to the invention thus also shows a clearly positive action on the ovary by stimulating the follicular maturation and therefore is also suitable for the treatment of female sub- or infertility.
Production of the Compounds According to the Invention
For the production of the compounds of general formula I according to the invention, primarily two synthesis strategies that can generally be applied are used.
On the one hand, in particular 3,16-protected derivatives of estra-1,3,5(10)-triene-3,16ξ-diols, but also optionally the free diols, can be used for modifications of individual positions of the steroid skeleton.
On the other hand, correspondingly modified estrone analogs, which can be obtained in large numbers in known ways [for a typical synthesis process, see J. Chem. Soc. Perk. 1, 1973, 2095 for C(9); Steroids 54, 1989, 71 for C(7)], include a flexible access to the compounds according to the invention by transposition of oxygen functionality (Z. Chem. 1970, 221) from C(17) to C(16).
For the case of the 3-methyl ether, after the ketone is converted into a sulfonyl hydrazone, the formation of the C(16)-C(17) olefin (Z. Chem. 1970, 10, 221 ff; Liebigs Ann. Chem. 1981, 1973 ff), in which hypobromide is stored in a regio-/stereo-controlled way, is carried out in the simplest case by reaction with phenyl sulfonylhydrazide, in a degradation reaction. Reductive dehalogenation and removal of the protective group of C(3) yield the 16β-alcohol, which can be converted according to known methods into the 16α-epimer.
Another variant for the introduction of the hydroxyl group at C-atom 16 is in the hydroboration of the 16(17)-double bond with sterically exacting boranes. It is known of this reaction that it results in 16-oxidized products (Indian J. Chem. 1971, 9, 287-8). Consequently, the reaction of estra-1,3,5(10), 16-tetraenes with, for example, 9-borabicyclo[3,3,1]nonane after oxidation with alkaline hydrogen peroxide yields 16α-hydroxyestratrienes. To a lesser extent, the epimeric 16β-hydroxy steroids are formed in this reaction. After the cleavage of the 3-methoxy group, estra-1,3,5(10)-triene-3,16α-diols are obtained. By inversion of the configuration at C-atom 16, e.g., by Mitsunobu reaction (synthesis 1980, 1), in turn the 16β-hydroxyestratrienes are obtained.
For further production possibilities of the C(16)-C(17) olefinic intermediate stage, see also DE 199 06 159 A1.
The introduction of fluorine substituents is carried out via nucleophilic substitution reactions of hydroxyl groups with fluoroamine reagents (Org. React. 1974, 21, 158-173). If the hydroxyl groups are converted into the corresponding tosylates in advance, then the fluorinated compounds are obtained by reaction with tetra-n-butylammonium fluoride (J. Chem. Res. (M) 1979, pp. 4728-4755). Fluorine compounds are also accessible by reaction of corresponding alcohols with diethylamino sulfur trifluoride (DAST) (U.S. Pat. No. 3,976,691). Geminal difluorine compounds are produced, for example, by reaction of carbonyl compounds with sulfur tetrafluoride (U.S. Pat. No. 3,413,321) or diethylamino sulfur trifluoride (DAST) (U.S. Pat. No. 3,979,691).
For synthesis of the 9α-substituted 17β-fluoroestra-1,3,5(10)-triene-3,16-diols according to the invention, 17-oxo-estra1,3,5(10)-trienes are converted into the 17,17-difluoroestra-1,3,5(10)-trienes (U.S. Pat. No. 3,976,691). The thus accessible 17,17-difluoroestra-1,3,5(10)-trienes are converted by treatment with aluminum oxide into 17-fluoroestra-1,3,5(10),16-tetraene (U.S. Pat. No. 3,413,321). Another possibility for the production of fluoro-olefins exists in the reaction of the corresponding ketones with diethylamino sulfur trifluoride (DAST) in the presence of polar catalysts, such as fuming sulfuric acid (U.S. Pat. No. 4,212,815). The reaction of 17-fluoroestra-1,3,5(10),16-tetraenes with boranes and subsequent oxidation with alkaline hydrogen peroxide yields the 17β-fluoroestra-1,3,5(10)-trien-16α-ols (Org. React. 1963, 13, 1-54).
Access to the 9α-alkenyl- or 9α-alkinyl-substituted estra-1,3,5(10)-triene-3,16α-diols according to the invention is carried out first from the 3,16-dihydroxy-estra-1,3,5(10)-trienes that are protected in 3- and 16-position. By reaction with trimethyl silyl cyanide in the presence of lithium perchlorate, the regio- and stereoselective introduction of a 9α-cyano grouping (Synlett, 1992, 821-2) is carried out. After the protective groups are cleaved, the 9α-cyano compound is converted by reduction first into a 9α-formyl compound and then by a Wittig reaction (Org. React. Vol. 14, 270) into the 9α-alkenyl- or 9α-alkinyl-substituted compound.
The estratriene sulfamates according to the invention are accessible in a way that is known in the art from the corresponding hydroxy steroids by esterification with sulfamoyl chlorides in the presence of a base [Z. Chem. 15, 270-272 (1975); Steroids 61, 710-717 (1996)].
Subsequent acylation of the sulfamate group results in the (N-acyl)sulfamates according to the invention. For the (N-acryl)sulfamates, pharmacokinetic advantages were already detected (cf. DE 195 40 233 A1).
The regioselective esterification of polyhydroxylated steroids with N-substituted and N-unsubstituted sulfamoyl chlorides is carried out after partial protection of those hydroxyl groups that are to remain unesterified. Silyl ethers have turned out to be protective groups with selective reactivity that is suitable for this purpose since these silyl ethers are stable under the conditions of sulfamate formation, and the sulfamate group remains intact when the silyl ether(s) is (are) again cleaved for regeneration of the (residual) hydroxyl group(s) still contained in the molecule (Steroids 61, 710-717 (1996)).
The production of the sulfamates according to the invention with an additional hydroxyl group in the molecule is also possible in that the starting material is suitable hydroxy-steroid ketones. First, depending on the goal, one or more hydroxyl groups that are present are subjected to sulfamoylation. Then, the sulfamate groups optionally can be converted with a desired acyl chloride in the presence of a base into the (N-acyl)sulfamates in question. The now present oxosulfamates or oxo-(N-acyl)sulfamates are converted by reduction into the corresponding hydroxysulfamates or hydroxy-(N-acyl)sulfamates (Steroids 61, 710-717 (1996)). Sodium borohydride and the borane-dimethyl sulfide complex are considered as suitable reducing agents.
The examples below are used for a more detailed explanation of the invention.
Analogously to the degradation of the 9α-vinyl grouping, other compounds of general formula I can be obtained with use of reagents that are homologous to the reagents that are described in the examples.
Etherification and/or esterification of free hydroxy groups is carried out according to the methods that are common to one skilled in the art.